Oxidative stress and inflammation induced by environmental and psychological stressors: a biomarker perspective

[Significance]: The environment can elicit biological responses such as oxidative stress (OS) and inflammation as a consequence of chemical, physical, or psychological changes. As population studies are essential for establishing these environment-organism interactions, biomarkers of OS or inflammation are critical in formulating mechanistic hypotheses.
[Recent Advances]: By using examples of stress induced by various mechanisms, we focus on the biomarkers that have been used to assess OS and inflammation in these conditions. We discuss the difference between biomarkers that are the result of a chemical reaction (such as lipid peroxides or oxidized proteins that are a result of the reaction of molecules with reactive oxygen species) and those that represent the biological response to stress, such as the transcription factor NRF2 or inflammation and inflammatory cytokines.
[Critical Issues]: The high-throughput and holistic approaches to biomarker discovery used extensively in large-scale molecular epidemiological exposome are also discussed in the context of human exposure to environmental stressors.
[Future Directions]: We propose to consider the role of biomarkers as signs and to distinguish between signs that are just indicators of biological processes and proxies that one can interact with and modify the disease process.
L.S. is supported by an Integrative Toxicology Training Partnership (ITTP) PhD studentship from the Medical Research Council (MRC). A.H. is recipient of a PhD studentship from the BHF. A.C. and G.M. are funded by SAF2013-43271-R of the Spanish Ministry of Economy and Competitiveness and European Regional Development Fund, Competitiveness Operational Program 2014–2020, grant P_37_732/2016 REDBRAIN. D.B. is supported by the H2020 MSCA project PANDORA (GA 671881) and by the Cluster project Medintech granted by the Italian MIUR. A.H. is a recipient of a BHF PhD studentship.